• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.3
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• pp.247-253
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• 2013

This paper analyzes ship area network(SAN) with integrated gateway. For the analysis, this paper analyzes reference network architecture, end-to-end connection model, traffic model, and requirement of SAN. Also, the type of network element and minimum performance of integrated gateway is derived by ship area network simulator. The performance evaluation results show that a integrated gateway operating as network switch with performance over than 30,000 packets/sec can provides end-to-end connection with satisfaction of requirement of each end-to-end connection.

• Journal of KIISE:Information Networking
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• v.36 no.3
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• pp.184-190
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• 2009

WiBro has advantages when both WLAN and 3G UMTS are adopted. Much research is being carried out in this area. However, the WiBro specification does not consider end-to-end security. Hence, another security protocol has to be adopted to support secure communication. Most previous research only focused on WiBro MAC performance improvement or security. In this paper, we adopt a security protocol such as IPsec, TLS, and DTLS, well known end-to-end security protocols, to make full use of WiBro in the IP network. Using NS-2 we simulated the adoption of end-to-end security protocol and evaluated performance and usability. Simulation shows DTLS had some performance advantages. All the protocols, TLS and IPsec are also suitable for use in WiBro.

• International Journal of Automotive Technology
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• v.6 no.1
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• pp.71-77
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• 2005

This paper presents a systematic approach which determines the optimal period to minimize performance measure subject to the schedulability constraints of a real-time control system by formulating the scheduling problem as an optimal problem. The performance measure is derived from the summation of end-to-end response times of processed I/Os scheduled by the static cyclic method. The schedulability constraint is specified in terms of allowable resource utilization. At first, a uniprocessor case is considered and then it is extended to a distributed system connected through a communication link, local-inter network, UN. This approach is applied to the design of an automotive body control system in order to validate the feasibility through a real example. By using the approach, a set of optimal periods can easily be obtained without complex and advanced methods such as branch and bound (B&B) or simulated annealing.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.53 no.7
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• pp.501-508
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• 2004

In this paper, a coordinated scheduling algorithm is proposed to reduce end-to-end delay in distributed control of systems. For the algorithm, the analysis of practical end-to-end delay in the worst case is performed priory with considering implementation of the systems. The end-to-end delay is composed of the delay caused by multi-task scheduling of operating systems, the delay caused by network communications, and the delay caused by asynchronous timing between operating systems and network communications. Through some simulation tests based on CAN(Controller Area Network), the proposed worst case end-to-end delay analysis is validated. Through the simulation tests, it is also shown that a real-time distributed control system designed to existing worst case delay cannot guarantee end-to-end time constraints. With the analysis, a coordinated scheduling algorithm is proposed here. The coordinated scheduling algorithm is focused on the reduction of the delay caused by asynchronous timing between operating systems and network communications. Online deadline assignment strategy is proposed for the scheduling. The performance enhancement of the distributed control systems by the scheduling algorithm is shown through simulation tests.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.05b
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• pp.25-29
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• 2004

Corona on polymer materials causes deterioration by the combined action of the discharge striking the surface and the action of certain chemical compounds that are formed by the discharges. In the design and manufacture of polymer insulators must be sufficiently large to avoid corona discharges, otherwise a shielding or corona ring (grading ring) needs to be installed on the insulator. To conduct this purpose, many researchers have investigated end-fitting of polymer insulator by voltage distribution simulation and electrical test. Grading rings are used to improve the performance of the insulator in multiple ways. They can reduce corona and associated audible noise and radio influence and television interference. The factors determining the uses of a grading ring are line voltage, geometry and dimensions of end fittings, geometry and dimensions of line hardware, and environmental conditions. In this paper, electrical property of polymer insulator with end-fitting design have been investigated by electrical field analysis, various end-fitting design, tracking wheel test, corona inception voltage and extinction voltage. Electrical field analysis is conducted by FEM program and various end-fitting is designed through this result. Designed end-fittings are manufactured and their performance is conducted by electrical performance test.

• The Journal of the Convergence on Culture Technology
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• v.7 no.3
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• pp.135-146
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• 2021

This study is a descriptive research study to identify the relationship between the performance of end-of-Life care of ICU nurses, moral distress, ethical climate, difficulties in end-of-life care, and positive psychological capital. Data were collected with structured questionnaires from 144 ICU nurses at a university hospital in J city, Gyeongnam, from October to November in 2020, and analyzed using SPSS/WIN 21.0. The subjects' performance of end-of-life care of ICU nurses is significantly different depending on marital status, experiences of end-of-life care education. The variables that had a significant effect on the performance of end-of-life care among ICU nurses were positive psychological capital and difficulties in end-of-life care. The explanatory power was 24.8%. Based on these results, it is necessary to intervention program and education to reduce difficulties in end-of-life care and increase positive psychological capital for ICU nurses.

• Journal of Korean Critical Care Nursing
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• v.14 no.1
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• pp.1-13
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• 2021

Purpose : Based on Quint's theory and the relevant literature, this study constructed a structural equation model for explaining and predicting end-of-life care performance in clinical nurses. Methods : A self-administered questionnaire was used to collect data from 265 nurses between September 1 and September 30, 2016. The data were analyzed using SPSS ver. 21 and AMOS ver. 21. Results : The goodness of fit of the modified model was found to be relatively satisfactory (χ2=114.82, Nomed χ2(χ2/df)=2.44, SRMR=.06, GFI=.94, AGFI=.89, CFI=.95, TLI=.91, RMSEA=.07). End-of-life care performance was affected by the attitudes toward nursing care of the dying, working unit, and death anxiety. The attitudes toward such care had the highest effect on end-of-life care performance. Conclusion : The results suggest that end-of-life care performance is directly and indirectly affected by attitudes toward nursing care of the dying, participation in end-of-life care education, working unit, death perception, and death anxiety. To improve clinical nurses' end-of-life care performance, effective programs to promote death anxiety and attitudes toward nursing care of the dying need to be developed. In addition, hospital nursing organizations should attempt to produce concrete measures for death anxiety and terminal care attitudes in clinical nurses.

• Journal of Astronomy and Space Sciences
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• v.24 no.1
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• pp.69-78
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• 2007

The international EARTHSHINE mission is to measure 1% anomaly of the Earth global albedo and total solar irradiance using Amon-Ra instrument around Lagrange point 1. We developed a new ray truing based integrated end-to-end simulation tool that overcomes the shortcomings of the existing end-to-end performance simulation techniques. We then studied the in-orbit radiometric performance of the breadboard Anon-Ra visible channel optical system. The TSI variation and the Earth albedo anomaly, reported elsewhere, were used as the key input variables in the simulation. The output flux at the instrument focal plane confirms that the integrated ray tracing based end-to-end science simulation delivers the correct level of incident power to the Amon-Ra instrument well within the required measurement error budget of better than ${\pm}0.28%$. Using the global angular distribution model (ADM), the incident flux is then used to estimate the Earth global albedo and the TSI variation, confirming the validity of the primary science cases at the L1 halo orbit. These results imply that the integrated end-to-end ray tracing technique, reported here, can serve as an effective and powerful building block of the on-line science analysis tool in support of the international EARTHSHINE mission currently being developed.

• Journal of Hospice and Palliative Care
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• v.21 no.4
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• pp.124-136
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• 2018

Purpose: This descriptive study is aimed at identifying how nursing hospital workers' performance of end-of-life care is influenced by their knowledge and awareness of hospice palliative care, attitude towards end-of-life care, performance, importance, awareness of death and the factors. Methods: A self-reported questionnaire was used to collect data from 113 workers at an accredited nursing hospital in K province. Variables were their knowledge and awareness of hospice palliative care, attitude towards end-of-life care, end-of-life care performance and importance and awareness of death. An analysis was performed with the frequency, percentage, mean, standard deviation, t-test, ANOVA, Scheffe's test, Pearson's correlation coefficient and multiple regression using IBM SPSS 21.0. Results: The factors affecting the nursing hospital workers' end-of-life care performance were the importance of end-of-life care and their marital status, which showed an explanatory power of 38.2%. Conclusion: In order to improve the nursing hospital workers' end-of-life care performance, a training on the importance of end-of-life care should be provided. Therefore, we would like to propose establishing administrative measures such as 1) efficient staffing to help the caregivers better perform what they think is important, 2) development of a training program that can improve their performance of end-of-life nursing care and 3) a study to verify the effectiveness of the program.

• Journal of the Korea Institute of Military Science and Technology
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• v.11 no.1
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• pp.15-24
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• 2008

The data delivery confirmation method of MIL-STD-188-220C, which is a tactical wireless mobile Ad-Hoc communication protocol, is that a source node requires the end-to-end ack from all destination nodes and the data-link ack from 1-hop neighboring destination nodes and relaying nodes, regardless of the hop distance from a source node to destination nodes. This method has the problem to degrade the whole communication network performance because of excessive data traffic due to the duplicate use of end-to-end ack and data-link ack, and the collision among end-to-end acks on the wireless network in the case of confirming a data delivery within an 1-hop distance. In order to solve this problem, this paper has proposed the method to perform the data delivery confirmation with the improvement of communication network performance through the data traffic reduction by achieving the reliable data delivery confirmation requiring the only data-link ack within an 1-hop distance. The effects of the proposed method are analyzed in the two aspects of the data delivery confirmation delay time and the data delivery confirmation success ratio.